Solid-state batteries and methods of making solid-state batteries

Abstract

Described herein are examples of solid-state batteries. The solid-state battery can include a cathode prepared from graphene, sulfur and phosphorus, an anode prepared from silicon and lithium, and a separator prepared from an ion-conducting material. The solid-state battery can further include current collectors and housings to prepare the solid-state battery. The main elements (cathode, separator, and anode) can be selectively blended together to avoid the problems of a hard interface and to provide more efficient performance. The method of building the battery can be instrumental in simplifying the manufacturing process in next-generation factories. The solid-state batteries can be prepared without liquid electrolytes by substituting solid electrolyte particles into the electrode material itself, or by other means, resulting in safer, smaller and easier to manufacture batteries.

What is claimed is: 
     
         1 . A device comprising:
 a cathode comprising:
 graphene; 
 sulfur; and 
 phosphorus, wherein:
 the graphene comprises between 2 and 50 layers of graphene sheets; 
 the sulfur is covalently bonded to the graphene; and 
 the phosphorus is bonded to the sulfur; 
 
   an anode comprising silicon and lithium;   a separator comprising an ion-conductive material and a binder, wherein:
 the ion-conductive material is a lithium sulfur phosphate Li 6 PS 5 Cl, or other argyrodite; and 
 the separator is located between the anode and the cathode; 
 a first current collector and a second current collector, wherein: 
 the first current collector is copper and affixed to the anode; and 
 the second current collector is aluminum and affixed to the cathode; and 
   a first housing and a second housing, wherein:
 the first housing is affixed to the anode, and the second housing is affixed to the cathode; and 
 the device is a solid-state battery comprising one of no liquid electrolyte and a liquid electrolyte. 
   
     
     
         2 . The device of  claim 1 , wherein:
 the graphene is 10-60% of the cathode by weight;   the sulfur is 30-80% of the cathode by weight;   the phosphorus is 1-10% of the cathode by weight; and   the graphene is an edge functionalized graphene comprising 2-50 sheets of graphene.   
     
     
         3 . The device of  claim 2 , wherein:
 the edge functionalized graphene comprises edge functionalized graphene that is covalently bonded to sulfur and edge functionalized graphene without sulfur.   
     
     
         4 . The device of  claim 1 , wherein:
 the separator has a thickness between 1 to 50 μm;   the cathode has a thickness between 65 and 400 μm; and   the sulfur comprises chains from SLi 2  to S 8 Li 6  covalently bonded to the graphene.   
     
     
         5 . The device of  claim 1 , wherein:
 the cathode further comprises an ion-conductive material dispersed in the cathode;   the ion-conductive material is lithium tin phosphorus sulfide or lithium phosphorus sulfur chloride; and   the ion-conductive material is configured to increase electron and ion flow within the cathode.   
     
     
         6 . The device of  claim 1  wherein the sulfur is S 2 -S 8  milled to a uniform sub-micron particle size and cross-links the graphene sheets.